Abstract Nanoparticle biosynthesis has attained a lot of attention because of its cost-efficiency and eco-friendly process. Only limited studies are available which explain the interrelationship between physical parameters (pH, gold concentration, extract concentration, and temperature) and biological synthesis mechanism. The goal of this study was to predict the antioxidant as well as anti-inflammatory activity of biosynthesized gold nanoparticles utilizing Citrus sinensis peel extract. The initial colour shift from yellow to ruby red served as proof that nanoparticles had been successfully synthesized. The nanoparticles that were synthesized underwent various characterization techniques such as AFM (Atomic Force Microscope), FTIR (Fourier Transform Infrared Spectroscopy), FESEM (Field Emission Scanning Electron Microscope), XRD (X-Ray Diffraction), and UV–vis spectroscopy to examine their properties. Further, the synthesis method was optimized for different pH, various gold concentrations, extract concentrations, and temperatures. The nanoparticles displayed good activity as a powerful antioxidant and anti-inflammatory agent. Advanced studies are necessary to explore their therapeutic property.